noun
Mara; demon king
In Buddhism, the demon king who tempted Gautama Buddha and represents the forces that hinder enlightenment.
from Sanskrit māra
仏教では、魔羅は悟りを妨げる存在とされる。
In Buddhism, Mara is considered a being that obstructs enlightenment.
noun
obstacle to enlightenment
Extended Buddhist use: anything that hinders spiritual progress, not just the personified demon.
欲望は魔羅となり得る。
Desire can become an obstacle to enlightenment.
noun
Colloquial, often vulgar slang for the male organ. Usually written in katakana as マラ.
あの単語はマラって意味だよ。
That word means penis.
Katakana spelling is usual for the colloquial 'penis' sense.
魔 is a broader term for demon, evil spirit, or obstacle, while 魔羅 specifically refers to the Buddhist demon king Mara or, colloquially, the penis.
From Sanskrit māra, via Buddhist texts. The colloquial 'penis' sense is a slang extension, possibly from the idea of a 'troublesome' organ.